Synchronized clock system and secondary clock therefor



Oct. 17, 1933.

S. H. CHAMBERLAIN, JR

SYNCHRONIZED CLOCK SYSTEM AND SECONDARY CLOCK THEREFOR Filed May- 2, 1929 Swuemtoz Patented Oct. 17,1933

j .UNITED STATES PATENT OFFICE w l1,931,019 K I l Samuel Harrison Chamberlain, Jr., East Orange,

N. J., assignor, by mesne assignments, to International Business Machines Corporation,

New York, N. Y., a corporation of New York.

g Application May 2, 1929. Serial No. 359,753 23 Claims. (CL 58-24).

This invention relates to improvements in synchronized clock systems and in master and secondary clocks therefor, and more particularly the invention relates to improvements in the system and clocks disclosed in the copending application'of James W. Bryce, Serial No. 17,683, led March 23, 1925, and in the system disclosed in Bryce and Getz Patent No. 1,740,330, dated December17, 1929.

Heretofore, synchronized clock systems with impulse actuated secondaries have been devised utilizing a single wire or line circuit intermediate the master clocks or secondary clocks. Certain of such systems have used variable voltage of the impulses for controlling the clocks and Aalso certain other systems have employed variable current frequencies for controlling the secondary clocks.

One object of the present invention resides in the provision of a system in which the normal and fast or accelerating impulses are sent out over a common line circuit or wire to the secondary clocks and in which release of the secondaries is effected by sending an additional supply of current over the same Wire which transmits the impulse to the secondary clocks. Preferably such additional current supply is a sustained flow of current which sustained current when received by the secondaries releases the clocks to again permit their advance in synchronism with the master clock.

A further object of the present invention resides in the provision of. an impulse actuated secondary system in which secondary clocks are provided with means which is effective to restrain the impulse advance of the clocks under certain conditions and in which means is provided to remove such restraint by providing for a sustained current flow over the impulse circuit to the clocks.

A further object of the present invention resides in the provision of an improved secondary clock construction in which thermostatic means is provided in the secondary clocks for effecting the release of clocks whose action has been restrained. f

Further and other objects of the present invention will be hereinafter set forth in the accompanying specification and claims and shown in the drawing which by way of illustration are what I now consider to be a preferred embodiment of the invention.

In the drawing: y

Figure l is a diagram of a clock system incon- 50 porating my improvements;

Fig. 2 is a detail view of a part of the controiliingkdevice which is disposed in each secondary c oc In the diagram there is shown a master clock which is of any conventional type with the usual 00 time train which drives a minute arbor 10 to cause it to make one revolution for example, once per hour. On this arbor there are two cams 12 and 15. 15 controls contacts 16 and 12 controls contacts 14.v Preferably 16 closes 50 65 seconds before the hour or before the th minute as determined by the master clock and 14 closes 20 seconds before the hour and opens at the hour. The time train also drives a minute cam 18 which actuates minute contacts 17. 11 70 is the usual verge or escapement whichv operates .rapidly acting contacts 19. G is the ground.

32 a switch and 34 a relay which when energized closes contacts'35. 37 is the line circuit which extends to the secondary clocks.

The action of the master clock in the sending out of impulses and controlling current flow over the line 37 to the secondaries is as follows:

A For transmitting normal impulses, current flows from G through the battery B, through switch 32, through 17 which closes once a minute, through 34 and back to ground. Energization of 34 closes relay contacts 35 so that impulses flow from the battery B, through 35, through line 37 to the various secondaries and back to the battery through ground G. When contacts 16 close, more rapidly recurring impulses are sent by 19 to relay 34. The rapid action of this relay thus sends out a number of rapid impulses to the line 37 and to the secondaries.

The secondary clocks comprise the usual minute arbor 20 provided with ratchet wheel 22 operated by spring return pawl devices 21a from impulse magnet 21. This is the conventional impulse secondary construction. Disposed upon each ratchet wheel 22 is a stop or abutment member 50. Fixed in each secondary is a suitable bimetallic thermostat device 51 (see Fig. 2). This thermostat is in such position that it may engage the abutment 50 and prevent further advance 100 of a secondary clock notwithstanding that impulses are received by the impulse magnet and continue to impose such restraint against impulse advance until the bi-metallic thermostat has been flexed to one side and cleared of (see the dotted line position of the parts in Fig. 2). The location of the thermostat and of the abutment is such that each clock arrested when the minute hand of such secondary clock stands at 60 or upon the even hour.

the abutment ToV flex the thermostat a heating coil 52 is provided which heating coil is connected in series with the impulse magnet 21. The arrangement and proportions of the heating coil and thermostat is such that the momentary impulses do not heat up the thermostat sufficiently to cause it to iiex clear of the abutment but sustained current flow over line 37 attendant upon the closure of contacts 14 heats the thermostat suiciently to flex it to clear position.

The action may be summarized as follows: For clocks which are fast advance of the clock continues until the thermostat 51 engages the abutment 50 to stop further advance of the clock. For clocks which are slow the rapid impulses step up the clocks until 51 engages 50 whereupon further advance is prevented. For clocks which are on time there is also a restraint imposed by the thermostat 51 which prevents advance o! such on time clocks past the 60th 'minute position which advance would occur on account of the additional fast impulses being received over line 37. At 20 seconds before the hour as indicated by the hands of the master clock, contacts 14 close. The closure of these contacts permits a sustained ow of current to flow through the contacts through the coil 34 and the coil 34 thus remains energized for a twenty second period, and accordingly contacts 35 remain closed for a 20 second period. The sustained current flow goes over line 37 to the secondary clocks, causes the energization of the impulse magnet 21 of each clock and also the efl'ect of the sustained current flow is such that the heating coil 52 can heat up the thermostat so that it exes to the dotted line position of Fig. 2. When the sustained current flow is cut off, the line circuit to the secondaries will again be interrupted causing a de-energization of 21 and causing the spring restored pawl devices 21a to again step ahead or advance the clocks so that abutment 50 will pass under the thermostat. The succeeding impulses again carry the clock forward in the usual manner.

What I claim is:

1. A secondary clock including an impulse magnet, parts adapted for advance under the control of said magnet and means for restraining said parts against advance, said last mentioned means including a thermostatic device for rendering the restraining means ineffective.

2. A secondary clock including an impulse magnet, parts adapted for advance under the control of said magnet, and a thermostatic device having a heating coil disposed in circuit with said magnet with provisions for restraining advance of said parts until effective heating of the thermostatic device by said coil has taken place.

3. In a synchronized clock system of the impulse type wherein there is a single line circuit intermediate the master clocks and the secondaries which transmits all actuating impulses and all controlling current supply to the secondary clocks and including in combination therewith of means in a secondary clock for restraining its impulse advance under certain chronological conditions of the clock with respect to the master clock. and means effective upon a sustained flow of current over the line which transmits the impulses for removing the restraining means from restraining position sothat a previously restrained clock can resume its advance.

4. A synchronized clock system including a secondary clock provided with an impulse magnet and having a heating coil in series with SW3! magnet and restraining means affected by said heating coil and adapted when in one position to restrain impulse advance of the clock and when in the other position to permit advance of the clock.

5. A synchronized clock system including a master clock with means therein to impart to a single common line circuit, normal impulses, fast impulses and for a given time and periodically a sustained current flow which has a longer time of flow than the time of iiow of said impulses, one or more secondary clocks connected to said line, and means in the secondary clock for restraining impulse advance' under certain chronological conditions of each clock, means for permitting impulse advance under other chronological conditions of the clock, and means for removing the restraining means to a position under which no restraint is imposed thereby when the sustained current flow is received from the master clock.

6. A synchronized clock system including a master clock and one or more secondary clocks and a single line circuit connecting the master clock and al1 of the clocks, means in the master clock for sending out thereof the normal actuating impulses the more rapidly recurring stepping up accelerating impulses and for periodically sending out a sustained flow of current all over the same single common line circuit, and means in a secondary clock for restraining the clock against advance until said clock has received the steady flow of current over the common line circuit whereupon restraint to further advance is removed.

7. The invention set forth in claim 6 in which the'means in the secondary clock comprises a thermostatic device having a heating coil and which is displaced from restraining position by the steady flow of current through the heating coil.

8. The invention set forth in claim 6 in which each secondary clock is provided with an impulse magnet having a winding and in which a heating coil is provided in series with said winding and including a thermostatic device in proximity to said heating coil, said thermostatic device being flexed from one position to another by the heat from said coil and when in one position restraining the clock against advance and in the other position relieving such restraint.

9. A secondary clock including an impulse magnet and a circuit therefor, parts adapted for advance under the control of such magnet, a restraining means to prevent advance of such clock under a certain chronological condition of the clock, and means controlled by a relatively prolonged impulse flowing in the same direction as that of the advancing impulse through the impulse magnet circuit for disabling the restraining action of such means.

10. A secondary clock of the impulse type including means for mechanically restraining the clock against advance beyond a determined time, and means in the secondary clock which is susceptible only to prolonged current flow of the same current intensity as of the advancing impulses for displacing the restraining means to non-restraining position.

11. A secondary clock for use in a single circuit impulse clock system in which operation and synchronization of the secondary clock is effected over the single circuit from the master clock, mechanical restraining means in the clock for mechanically blocking its advance beyond a determined time point, and means for removing said mechanical means from restraining position, said means including a means which is effectively susceptible to an impulse oi relatively increased duration only.

12. A single circuit secondary impulse clock with an impulse magnet permanently connected in a single circuit so as to be affectedby all impulses ilowing in the circuit, and synchronizingv means including a device which is always permanently in the single circuit with the impulse magnet, which device is effectively actuated only by certain impulses ilowing over the circuit, which certain impulses have a relatively prolonged duration with respect to the other impulses.

13. A secondary clock of the impulse type including an impulse magnet in an impulse magnet circuit of the clock, an impulse actuated part and a controlling means for said impulse actuated part to stop or permit advance of said part, said controlling means including means affected by current flow in the impulse magnet circuit of the clock and which means by its position distinguishes impulses of a normal duration from impulses of prolonged duration which flow in the same impulse magnet circuit of the clock, said means also including a part which is displaced so as to be effective to permit advance of the impulse actuated part only by prolonged impulses.

14. A synchronized clock system including a master clock and one or more secondary clocks and a single line circuit connecting the master clock and the secondary clocks, means in the master clock for sending out therefrom impulses each of normal duration and for periodically sending out from the master clock a special impulse of relatively diierent duration with respect to the other previously mentioned impulses all over the single common line circuit, and meansin a secondary clock for compelling its synchronization from the master clock, said means including means for stopping a secondary clock and also including a device at the secondary clock which acts diferently so as to disregard the impulses of normal duration and to detect impulses of diierent duration and to bring about reinitiation of impulse advance of the secondary clock in synchronism with the master clock when the impulses of relatively different duration have been detected.

15. A synchronized clock system including a master clock and one or more secondary clocks and a single line circuit connecting the master clock and the secondary clocks, means in the master clock for sending out therefrom impulses each of normal duration and for periodically' sending out from the master clock a special impulse of relatively different duration with respect to the previously mentioned impulses all over the single common line circuit, clock-controlling means in each secondary clock which are effective upon receipt of all impulses to attempt to advance the clock, and other clock-controlling means in each secondary clock which are effective only upon receipt of-impulses of a special and diierent duration from the normal impulses to permit reinitiated advance of the clock under the control of the last mentioned means.

16. A synchronized clock system including a master clock, and one or more secondary clocks electrically connected to the master clock and receiving impulses therefrom, means in the mas ter clock for sending out a series of normal impulses each of a given normal duration and for also periodically sending out to the secondary clocks sets of accelerating impulses each of the same normal duration and for further sending out to the secondary clocks a special impulse of a relatively different duration with respectto the previously mentioned impulses, impulse magnet means at each secondary clock for affecting impulse advance of the secondaries, means at each secondary clock for a time stopping its impulse advance, and means associated with the foregoing last mentioned means at each secondary clock and acting differently under the inuence of impulses of one duration or another and being thus adapted to detect the impulse oi different duration from the other impulses and upon effective action upon vreceipt of such impulse of different duration affecting the stopping means and permitting reinitiated advance of the secondary clock by the impulse magnet means in synchronism with the master clock.

f 1'7. A secondary clock comprising in combination, advancing means including an impulse magnet adapted to be energized from an impulse magnet circuit, and means, including a part which has a delayed action, for controlling the effectiveness and ineffectiveness of said advancing means according to whether impulses of normal duration or longer duration are supplied to the impulse magnet circuit.

18. Secondary clock synchronizing means comprising in combination, clock-controlled means for suspending advance of the clock, and

means unresponsive to clock-advancing current for, clock-controlled means for stopping the clock when fast, and a delayed response device associated with the impulse magnet circuit of the clock for releasing the clock only after receipt of a prolonged impulse in the impulse magnet circuit.

20. A secondary clock comprising in combination, time-indicating mechanism, step-by-step means including an impulse magnet for advancing said time-indicating mechanism, and means including a translating device operating with a sluggish action, electrically connected to said impulse magnet to be simultaneously energized therewith, for suspending advance of said mechanism by said step-by-step means when said magnet and device receive only intermittent current impulses each of comparatively short duration and for permitting continued advance of said mechanism by said step-by-step means when said magnet and device receive a current impulse of comparatively long duration.

21. A secondary clock comprising in combination, time-indicating mechanism, means for advancing said time-indicating mechanism in response to electric current impulses of short duration, means for suspending advance of said time-indicating mechanism by said firstnamed means, and means including a translating device operating with a sluggish action and responsive to an electric current flow of more prolonged duration than that of the aforesaid impulses for rendering said second mentioned means ineffective to suspend advance of said time-indicating means by said first named means.

22. In a secondary clock, in combination, ad' vancing means including an impulse magnet,

'and means including a translating device opera translating device unresponsive when energized by the interrupted advancing current to provide one control over the action of the time indicating means and responsive to current impulses of diiIerent duration to provide a dinerent control over the action or the time indicating means, both of said different controls cooperating for eiecting synchronization of the time indicating means.

SAMUEL HARRISON CHAMBERLAIN, Jl. 

